This application relates to an electrical device, and in particular, to a reactor.
Ballasts, such as reactor ballasts, are typically used to limit the current through or stabilize the operating of various light fixtures, such as high intensity discharge (HID) lamps. Lamps have specific ballasting requirements, such as operating current at the nominal lamp voltage and maximum starting current, which affect the ballast design. Depending upon the materials used and the ballasting requirements, the design considerations include core cross-section, total air gap, lamination thickness, the dimensions of the lamination, the electrical properties of the material, the number of turns of wire, the type of wire, the cross-sectional area of the wire, the number of laminations used, and the bobbin dimensions. Thus, it would be ideal to vary any or all of these variables freely, i.e., at will with little or no penalty on tooling, for various reasons. Such reasons may include accommodating new lamp designs, new specifications on power loss, material availability, and material price fluctuations.
Typical HID reactor ballast designs are based on laminations with an xe2x80x9cE-Ixe2x80x9d or an xe2x80x9cE-Exe2x80x9d structure. Bobbins or tape wound coils are used, and the bobbin or the tape serves as an electrical insulator between the magnetic wire and the steel core. Changes in the design of typical HID reactor ballasts to accommodate alternative materials or requirements may be difficult and expensive because typical HID reactor ballasts are generally very highly tooled devices that are not flexible with respect to design changes. Further, because ballast lamination and bobbin tools are generally very expensive, the initial startup manufacturing costs for reactor ballasts may be very high.
Accordingly, a need exists for a less expensive and flexible reactor ballast design.
An exemplary embodiment of the invention concerns a reactor. The reactor includes a core having an I portion and a rolled portion which forms a core opening, a coil having an electrically insulated coil opening through which the I portion extends, and a spacer between the I portion and a top edge of the rolled portion of the core. A portion of the coil extends into the core opening.
An additional embodiment of the invention concerns a ballast system. The ballast system includes a core having a plurality of I portions and a rolled portion which form one or more core openings, a plurality of coils, each coil having an electrically insulated coil opening through which one of the I portions extends, and a plurality of spacers between the I portions and a first edge of the rolled portion and between the I portions and a second edge of the rolled portion. A portion of each coil extends into a corresponding core opening.